The invention relates to closures. More particularly, the invention relates to tamper-evident screw cap closures for bottles and the like.
A well-developed art exists regarding tamper-evident screw cap closures. A typical closure is molded of a plastic material (e.g., polypropylene, low density polypropylene (LDPE), or high density polyethylene (HDPE)). The closure body typically comprises an internally threaded sidewall portion. A bottom of the sidewall forms a tamper-evident ring. There may be an interrupted or otherwise weakened connection between the ring and adjacent portion of the sidewall. At the upper end of the sidewall main portion, a web may close the closure. Alternatively, any of a number of forms of open valve seat may be formed to which a separate valve element (e.g., a poppet) is movably mounted to open and close the closure.
The closure may be installed to a threaded neck of the bottle by screwing/threading. The screwing may flex/stretch the ring over the bottle external threads. Upon unscrewing of the closure, however, the tensile strength of the connection may be insufficient to draw the ring back over the bottle threads, thereby rupturing the connection and leaving the ring on the bottle. Even upon reinstallation of the remaining portion of the closure, the severed connection provides clear evidence that the closure has previously been opened.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
Like reference numbers and designations in the various drawings indicate like elements.